Your vehicle oil and coolant levels should be at manufacturer's recommended levels.

Present your vehicle at normal operating temperature (generally driven for a minimum of 20 minutes). If you have to wait in line, keep your engine running.

Ensure the vehicle's emission control equipment is present and properly connected.

Make sure you have a properly fitting gas cap with no missing seal or seal cracks and breaks.

Make sure your check engine light is not lit while the engine is running or the light does not   fail   to illuminate, briefly, when you first turn on your vehicle.

If your vehicle does not pass the test, the Lane Operator will give you the failing Vehicle Inspection Report (VIR). It will show the areas where your vehicle did not pass. The Lane Operator will also give you an Authorized Emission Specialist List. These will assist you and your repair technician through the repair process. After necessary diagnostics and repairs are made to your vehicle, return to any testing facility for your retest. The first retest is free. Subsequent tests are not free.

Vehicle emissions pollute our air and create ground-level ozone, a major component of smog. The pollution ends up in our lungs, on the ground, on crops, and in our rivers and tributaries. Children, the elderly and people with breathing problems are most affected by air pollution; however, it is a health concern for all Sri Lankans.